Pain in undoubtedly the first symptom of corneal abrasion, especially when opening or closing the eye, and is often accompanied by foreign body sensation. If these symptoms are serious enough, patient daily life might be severely affected. Tearing is usually connected with these first symptoms, which can further be increased by the reflex tears production and the appearance of crusty buildups. Other signs are edema, conjunctival injection, mild anterior-chamber reaction, large pupils, swollen eyelids, and blurred vision.

Retracing the patient history is always useful, especially when the source of the injury is unknown or uncertain. Questions should be made to reveal the occurrence of any eye traumas in some related situation, such as sport activities, excessive eye rubbing or makeup applications. Gathering information about the patient history can be especially beneficial when episodes of recurrent corneal erosion syndrome [5] are involved, whose signs might take days or even years to appear.

Corneal abrasions can be easily detected by using slit lamps. If penetration of a retained foreign body is suspected, ocular CT scan, ocular MRI or both can be employed. Prolonged symptoms indicate the presence of corneal ulcers, which are duly confirmed with the use of bacterial cultures that allow the physician to choose the right antibiotic regimen.

Histopathological examination can detect the presence of intracellular and intercellular epithelial edema, which is usually associated with other complications like intraepithelial cysts or intermittent pyknotic nuclei. There might be the appearance of intraepithelial basement membrane formations and the basement membrane itself can appear thickened and multilaminar. Corneal abrasion can also cause the breakdown of the blood-aqueous barrier which causes the plasma proteins and inflammatory cells to enter the eye anterior chamber.

Patching can be used to help relieve the pain coming with corneal abrasions, even though its benefits are still under debate [6] [7] [8]. The main complication associated with patching is the risk of infection by the already mentioned pseudomonas aeruginosa. In fact, patching avoids tears formation and thus the flushing the eye surface to eliminate potential threatening pathogens.

An alternative to patching can be the use of diclofenac or ketorolac drops in addition to antibiotics [9] [10] [11]. Apart from avoiding infections, this therapy offers the further advantage of allowing a binocular vision during treatment. The use of prophylactic topical antibiotics is strongly recommended when abrasions are due to contact lenses, while in the worst cases of recurrent corneal erosion laser surgery can be effectively employed.

In general, there are some tips to follow to favor eye healing after an episode of corneal abrasion, like avoiding contact lenses use, wearing sunglasses and not rubbing the eye. There is no permanent damage in the cases of minor abrasion, but deeper scratches can develop other complications that if not quickly treated might result in long-term vision complications.

If prompt treatment is provided, the prognosis of corneal abrasion is generally very good. The healing period depends on the lesion gravity. Usually, it takes 1 to 2 day for minor abrasions to heal, while a week for more extensive and deeper ones.

Corneal abrasions can sometime be very risky and lead to severe complications, like blinding ulcers and permanent visual acuity losses (if the abrasion occurs directly over the pupil). Among the most devious complications there is the risk of recurrent epithelial erosions after some days or weeks from the first healing. This occurs when damage takes place on the basement membrane, to which the newly overlying cells do not perfectly adhere and over which they can slip. For this risk of subsequent complications check in follow-up is often necessary.

Corneal abrasion is the result of some type of trauma that the eye undergoes in traumatic situations, such as the already mentioned foreign bodies blowing into the eye or the presence of dirt or sand on the ocular surface. It is often hard to know what is the original cause of a corneal abrasion episode, since the symptoms not always appear immediately.

Mechanical injuries are perhaps the most frequent causes of corneal abrasions. Episodes like jabbing a finger into the eye or being hit by a flying sharp object are common events in daily life and might occur very frequently in certain situations. These include the practice of sports like soccer, where the ball impact causes one third of all major or minor eye damages happening in this athletic activity [1].

Wearing contact lenses is another common cause of corneal abrasion, especially when they are worn for far too long. Damage might often result upon lenses removal rather than lens placing. This is because for the insufficient blinking, the lens sometime becomes slightly dehydrated and begins to adhere very tightly to the cornea. In this condition, when the lens is removed the external epithelium might be removed with it. Furthermore, the caused abrasions are often not perceived by the subject, since the lens itself acts as bondage. This complication is particularly common for those who do not blink sufficiently or work in dry environments. Moreover, wearing the lens overnight might favor the development of infections, especially by the bacterium pseudomonas aeruginosa which thrives in the lens bio film. These circumstances can often be sight-threatening and for this they represent a major optical emergency.

Corneal dystrophy can be another common cause of corneal abrasions. It consists in the accumulation of amyloid deposits in the middle and anterior stroma, which results in the formation of overlapping dots and branching filaments. Over time these formations begin to spread and end up involving an increasingly larger part of the cornea, creating the conditions for a severely reduced vision. If these abnormal protein fibers accumulate under the cornea outer layer, they can also cause the epithelium erosion, which in turn alters the normal corneal curvature.

Corneal abrasions can be also frequent during surgery, for example when a suture is inadvertently placed on the tarsus. In this regard, particularly common are the possible complications associated with anesthesia, as this decreases tear production and increases the eye surface exposure to harmful mechanical stimuli.

As previously explained, corneal abrasions are the most common cause of eye injuries, especially in people who wear contact lenses. They account for approximately 10% of the eye-related emergency visits, with an incidence depending on factors such as the patient work environment and his daily routine.

Some studies conducted in the US appear to be very revealing from an epidemiologic point of view. According to a study conducted in 1985 in the offices of family practice clinicians, internists and pediatricians, the eye complaints represented 2% of the patient visits, and of these 8% were due to traumatic conditions and the presence of foreign bodies [2]. Eye damages also decrease productivity, with 65,000 work-related eye injuries occurring each year associated with a remarkable missed time in terms of productive capacity [3].

A study carried out in a major US automotive corporation reveals an annual incidence of 15 eye injuries per 1000 employees [4]. According to this particular study, a total of 1983 work-related eye injuries occurred between July 1989 and June 1992 at the plants of this corporation, with 86,7% of the cases due to foreign bodies and corneal abrasions [4]. One third of these cases resulted in the inability of the workers to resume their normal duties lasting for at least one day.

No major difference in corneal abrasion rates has been found among races, while medical treatments are more frequent among men than women. The incidence of corneal abrasions is higher among young people than among elderly, perhaps because the first conduct a more active life with a higher frequency of possible daily incidents.

A corneal abrasion is limited to the most superficial layer of the cornea and does not usually penetrate the Bowman membrane. However, in certain severe circumstances the corneal injury might involve the deeper and thicker stromal layer, giving rise to cases of ulcer.

Under normal circumstances, the corneal epithelial cells are constantly replenished by cells moving from the limbus and from the epithelium basal layer. In these conditions the limbal epithelium acts as a barrier to stop the migration of conjunctival epithelial cells into the cornea. When an injury occurs, the limbal cells begin to move towards the cornea center and replenish the damaged cells at the lesion site. A centripetal movement results from this migration, in which the cells advance in a coherent manner maintaining their relative positions. Actin might have an active role in this motion but with a mechanism which is not completely understood, as not completely understood is also the reason why the conjunctival epithelium is involved in the corneal wound response.

Wearing protective eyewear is a very effective method to reduce corneal abrasion risks, especially in dangerous occasions such as the practice of certain sports. Wearing goggles or sunglasses is also recommended, to reduce ultraviolet exposure and avoid possible corneal flash burns. Contact lens wearers should make sure to properly place the lenses on the eye surface and change them according to the provided recommendations.

Corneal abrasion occurs when a physical external force, caused for example by foreign bodies or a contact lens, disrupts the integrity of the corneal epithelium, which it turn scrapes away leaving behind an abrasion of variable size. This is a very common eye injury and generally heals very rapidly. However, in the most severe cases corneal abrasions might result in permanent damage such as scar formations.

Cornelian abrasion is a scratch of the transparent layer of the eye called cornea. It occurs when a physical external force, caused for example by foreign bodies or contact lens, disrupts the integrity of the cornelian epithelium. The corneal epithelium scrapes away and leave behind an abrasion of variable size which can cause severe and persistent pain. The occurrence of this ocular abrasions heavenly depends on the patient routine and his daily activities, but in general terms they tend to be more frequent in young people than in elderly, because of their more active lifestyle. No major difference in corneal abrasion rates has been found among races.

It is often hard to know what is the original cause of a corneal abrasion episode, since the symptoms not always appear immediately. The most common causes of corneal abrasions are mechanical traumas, together with contact lenses use and the surgery-related injuries, and their classical symptoms are pain, foreign-body sensation, excessive tearing and blurred vision. Wearing protective eyewear is the most recommended form of prevention against this type of eye complication.

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